package main

import (
    "fmt"
    "net"
    "time"
)
func main() {
    resp := ""
    fmt.Print("(c)lient or (s)erver ?")
    fmt.Scan(&resp)
    fmt.Println("")

    b := make([]byte, 512, 512)
    p := uint64(0)

    if resp == "s" {
        listener, err := net.Listen("tcp", "127.0.0.1:10000")
        if err == nil {
            conn, err := listener.Accept()
            if err == nil {
                t0 := time.Now()
                fmt.Println("new connection from", conn.RemoteAddr())
                for {
                    n, err := conn.Write(b)
                    if n < len(b) {
                        fmt.Println(n)
                    }
                    p += uint64(n)
                    if (p > 1000000000) || (err != nil) {
                        break
                    }
                }
                conn.Close()

                fmt.Println("sent", p, "in sec", time.Since(t0))
            }
        }
    } else if resp == "c" {
        conn, err := net.DialTimeout("tcp", "127.0.0.1:10000", 10*time.Second)
        if err == nil {
            for {
                n, err := conn.Read(b)
                if n < len(b) {
                    fmt.Println(n)
                }
                p += uint64(n)
                if err != nil {
                    break
                }
            }
            conn.Close()

            fmt.Println("recv total", p)
        }
    }
}